The bonded rare-earth permanent magnet has been widely used in electronic equipment, office automation, automobile and so on, especially micro and special electric machines due to its advantages of well formability, high dimensional precision, high magnetic properties or the like. In order to meet the requirements for equipment miniaturization, it is necessary to further optimize the performance of bonded magnetic powder which used in the material.
Currently, the widely used magnetic powder is NdFeB magnetic powder prepared by rapid quenching method. It is not suitable for requiring the performance of the material under harsh environment due to its poor corrosion resistance and temperature resistance. The samarium-iron-nitrogen permanent magnetic powder effectively overcomes the above problems. The magnetic energy product of the prepared magnetic powder is above 17MGOe, higher than the rapidly quenched NdFeB magnetic powder. Meanwhile, the corrosion resistance and temperature resistance of the prepared magnetic powder is better than the NdFeB, it is a relatively promising rear-earth permanent magnetic material which has attracted extensive attention.
U.S. Pat. No. 5,482,573 discloses a rare-earth permanent magnetic material with a component of R1xR2yAzM100-x-y-z, which occupies the position of rare-earth element by addition of R2, i.e., Zr, Hf, and Sc, reduces the average atomic radius of rare-earth atomic site, thus increasing the concentration of M in the main phase, while accelerating the formation of TbCu7 main phase.
U.S. Pat. No. 5,716,462 discloses a rare-earth permanent magnetic material with a component of R1xR2yBzAuM100-x-y-z-u, which improves the residual magnetism by addition of element B, while, accelerating the formation of TbCu7 main phase by addition of elements Zr, Hf and Sc. M is only Fe or FeCo.
U.S. Pat. No. 6,758,918 discloses a samarium-iron-nitrogen permanent magnetic material with a component of SmxFe100-x-y-vM1yNv, which improves the square degree and coercivity by addition of M1 which is Zr and Hf, while reducing rapid quenching wheel speed by changing preparation process and rapid quenching copper wheel material.
However, the experimenter finds in the research that when the samarium-iron alloy is prepared by the rapid quenching method, the viscosity of samarium-iron alloy is a principal problem. Since the viscosity of the samarium-iron alloy is too large, the samarium-iron alloy can not be spouted out stably and continuously during the preparation process, which affects the formation of amorphous TbCu7 during rapid quenching, and the samarium-iron-nitrogen permanent magnetic material with excellent performance cannot be prepared stably.